How to Survey Land with 18th Century Tools — Using the Gunter’s Rule

Using the Gunter’s Rule So how was multiplication done in the 18th Century.  Sure, you could and people did do long-hand multiplication just like you were taught in elementary school.  For example, we can multiply 384×56. The number with more digits is usually selected as the multiplicand: The long multiplication algorithm starts with multiplying the …

How to Survey Land with 18th Century Tools – Measuring Lines

Land surveys consist of six basic tasks: Determinizing your position on Earth using celestial navigation methodsMeasuring distances with a Gunter’s Chain.Measuring changes in elevation with a Range PoleMeasurement of directions and angles using a Compass.Drawing the map on a Plane Table, andComputing areas with basic plane geometry In this series we will discuss the fundamentals …

How to Survey Land with 18th Century Tools – The Tools

Land surveys consist of six basic tasks: Determinizing your position on Earth using celestial navigation methodsMeasuring distances with a Gunter’s Chain.Measuring changes in elevation with a Range PoleMeasurement of directions and angles using a Compass.Drawing the map on a Plane Table, andComputing areas with basic plane geometry In this series we will discuss the fundamentals …

The Surveyor’s Artificial Horizon

Much of what you read about celestial navigation is focused on ocean navigation where you have a reasonably unrestricted line of sight to the horizon. Terrestial navigators and surveyors often do not have this and must make adjustments in their technique. One very common approach is to use an ARTIFICIAL HORIZON. An “artificial horizon” is …

Colonial Surveyor – Determining your Position using Celestial Navigation

A sextant is an intimidating complex instrument.  It consists of an A-shaped frame with an apex of 60° on a sextant or 45° on an octant.  Along the rounded lower edge of the frame is an arc, the limb, that is marked with numbers for the degree of the angles that the sextant can measure. An index …

Vector Computations without the Benefit of Modern Trigonometry

Navigating from point to point is a relatively simple task for most surveyors or mariners.  You establish a compass bearing from where you are to your intended location then measure out the distance (or in the case of sailing a speed and a time) to the new location giving what we call today a vector.  …

A Short History of Mapmaking in the Americas

Maps of land surfaces and charts of the sea coasts are scaled down representations of the earth’s surface. They are ideal documents to prove that a discovery has taken place and provide the means for the exploration to be repeated by others.  They are tremendous assets to the military and are a great aid to …